MSE: Verify MediaLog events created by existing MP4 unit tests
Similar to previous changes r342861 and
https://codereview.chromium.org/1300943002/, this change updates media
unit tests to provide a StrictMock<MockMediaLog> to verify MediaLog
events produced with existing MSE MP4 unit tests. While log message
maintenance burden is increased, helpers are used to reduce that burden
while gaining improved resilience against logging regression.
This CL does not verify all possible MSE MP4 parser MEDIA_LOGs, just
those that are emitted by existing unit tests.
TEST=no regression
Review URL: https://codereview.chromium.org/1300013002
Cr-Commit-Position: refs/heads/master@{#345183}
4 files changed
